1. Field
The following description relates to an information storage medium, an apparatus for reproducing recordings, and a method for reproducing recordings.
2. Description of Related Art
Various methods such as a high density scheme, a multilayer scheme, or the like have been devised to implement a high capacity information storage medium (or data transmission through wired or wireless networks). Generally, in the information storage medium, a high capacity is accomplished based on a combination of both a high density per layer and multilayers.
FIG. 1 illustrates an example of a three layer information storage medium 100.
Referring to FIG. 1, the three layer information storage medium 100 includes a first recording layer 110, a second recording layer 120, and a third recording layer 130. Generally, a pickup records or reproduces data in each recording layer along a tracking direction. In response to the pickup moving from a current recording layer to another recording layer, an interlayer movement is performed. As illustrated in FIG. 1, during the interlayer movement, a pickup 140 moves from one recording layer to another recording layer within a same radius of each of the recording layers. For example, the pickup 140 moves from the first recording layer 110 to the second recording layer 120. In another example, the pickup 140 moves from the first recording layer 110 to the third recording layer 130. In this manner, because the pickup 140 moves, theoretically, between two recording layers within the same radius during the interlayer movement, an address of a recording layer to which the pickup 140 moves correspond to an address within the same radius of the other recording layer. However, as a practical matter, the address may not be correct for various reasons, for example, because of mechanical errors which may occur during the interlayer movement of the pickup 140, eccentricity of the medium 100, or the like. Therefore, there is a need for a method to correctly determine the address of a recording layer. In particular, in an information storage medium that includes multilayers, it is even more necessary to correctly determine the address of a recording layer during an interlayer movement between the multilayers.